The inhalation of smoke which is generated from a smoking preparation is known to be a health hazard. The smoke which results from the combustion of tobacco and tobacco substitutes contains carbon monoxide, hydrogen cyanide, formaldehyde, acrolein, nicotine, phenols, tars, polycyclic hydrocarbons, and other such toxic components. There has been sustained investigative effort to develop cigarette products and other manufactured smoking compositions which deliver smoke with a reduced content of toxic components.
U.S. Pat. No. 2,003,690 describes a tobacco composition containing an inorganic oxidizing agent which is capable of yielding its oxygen to afford more complete combustion of aldehyde and other products of partial combustion during smoking.
U.S. Pat. No. 3,338,246 describes a smoking tobacco preparation containing a catalyst composition consisting essentially of an absorbent and catalytically active metal having a vapor pressure below one atmosphere at 1000.degree. C. The objective of the patent invention is to provide a smoking preparation which on burning causes less irritation in the human body and yet retains a pleasant taste.
U.S. Pat. No. 3,472,237 describes a method of treating tobacco to diminish the carbon monoxide which is released during the smoking process, which method involves impregnating the tobacco with a metal oxide selected from iron, calcium and copper oxides. The metal oxide is employed in the form of an aqueous dispersion with a carrier selected from reducing sugars. As a subsequent step, the impregnated tobacco is irradiated with visible light in the range of 4000-7000 A and ultraviolet light below about 3400 A to form a photochemical non-staining complex of the tobacco and the metal oxide.
U.S. Pat. No. 3,572,348 describes a smoking preparation comprising tobacco and a zeolite material which effects a decrease in the amounts of polycyclic aromatic compounds produced by the pyrolytic reactions of tobacco. The zeolite material is of the Y-type structure, preferably at least partially exchanged with zinc ions or containing metallic palladium, or at least partially exchanged with zinc ions and containing metallic palladium or is partially polyvalent zinc cation exchanged and partially decationized and contains metallic palladium.
U.S. Pat. No. 3,893,464 describes a smoking composition containing tobacco, and a combination of a catalytic agent and a nitric oxide releasing additive for reducing the concentration of polycyclic aromatic hydrocarbons in generated tobacco smoke. Illustrative of the catalytic agent is zine oxide, and the nitric oxide releasing additive preferably is selected from magnesium, calcium and zinc nitrates.
U.S. Pat. No. 4,125,118 describes a smoking composition which has incorporated a catalytic quantity of a transition metal compound to reduce the amount of toxic materials in released smoke without adversely affecting the organoleptic properties of the smoking composition or its smoke. The transition metal compounds employed to reduce the toxic materials in the smoke of tobacco and tobacco substitutes are those that are capable of promoting the oxidation of the toxic materials and in which the toxic materials are at least moderately soluble. They include transition metal salts of monocarboxylic acids having 4-24 carbon atoms, overbased metal salts of these monocarboxylic acids, amine complexes of transition metal salts of these monocarboxylic acids, and mixtures thereof.
There is increasing public awareness and governmental concern with respect to the health hazards associated with the inhalation of smoke delivered by manufactured smoking products.
Accordingly, it is a main object of this invention to provide novel smoking preparations which deliver smoke of reduced toxicity under normal smoking conditions.
It is another object of this invention to provide smoking tobacco compositions which deliver mainstream smoke with a reduced tar and nicotine content, and with a substantially reduced carbon monoxide content. k
Other objects and advantages of the present invention shall become apparent from the accompanying description and examples.